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NXT Level Plus Coverage Calculator: How Many 55 lb Bags?
Enter your floor area and the average pour thickness to see how many 55 lb (25 kg) bags of NXT Level Plus to buy. LATICRETE's coverage chart gives 24 sq ft per bag at 1/4 inch; the calculator scales that figure to your thickness, which matches the 1/4, 1/2 and 2 inch rows exactly and stays slightly on the safe side of the others. The numbers come from the North American data sheet DS-505-1026. This page covers NXT Level Plus, not the 50 lb NXT Level, which has a different chart.
LATICRETE NXT Level Plus coverage
| Thickness | US | Metric |
|---|---|---|
| 0.125 in (3.2 mm) | 48 sq ft | 4.5 m² |
| 0.25 in (6.4 mm) | 24 sq ft | 2.2 m² |
| 0.5 in (12.7 mm) | 12 sq ft | 1.1 m² |
| 1 in (25.4 mm) | 6 sq ft | 0.6 m² |
| 2 in (50.8 mm) | 3 sq ft | 0.3 m² |
Source: LATICRETE Data Sheet: NXT Level Plus (North America, English), DS-505-1026, Revision DS-505-1026 (© 2026), linked from the laticrete.com product page, read 2026-10-19.
How the calculation works
bags = area × (1 + waste ÷ 100) × thickness ÷ (coverage at reference thickness × reference thickness), rounded up
Self-leveler volume scales with thickness: twice as thick needs twice as many bags. Low spots in the floor add to the real average thickness, so measure the deepest point and the average before you pour.
Worked example
A 250 sq ft floor poured 0.5 in thick with 10% extra: 275 sq ft to cover. One bag covers 24 sq ft at 0.25 in, so at 0.5 in it covers 24 × 0.25 ÷ 0.5 = 12 sq ft. 275 ÷ 12 = 22.92 bags, so buy 23 (1,265 lb).
LATICRETE NXT Level Plus key specs
| Product type | Self-leveling underlayment |
|---|---|
| Bag size | 55 lb (25 kg) |
| Mixing water per bag (max) | 5.5 US qt (5.2 L) |
| Thickness range | 0.125–2 in |
| Coverage (data sheet) | 24 sq ft (2.3 m²) per 55 lb bag at 1/4" (6 mm); 49 at 1/8", 12 at 1/2", 8.1 at 3/4", 6.1 at 1", 3.0 at 2" (51 mm) |
| Mixing water | 5.0–5.5 US qt (4.7–5.2 L) per 55 lb bag; do not overwater |
| Pour depth | concrete 1/8" to 2" (3 to 51 mm), tapered to zero at edges; plywood/OSB 1/4" to 2" (6 to 51 mm); over STRATA_MAT or STRATA_HEAT Mat at least 1/2" (12 mm); ask LATICRETE Technical Services for pours over 2" |
| Wood subfloors | no metal lath needed over APA-rated exterior-glue plywood or OSB (interior only); maximum deflection L/360 (ASTM F2873); thicker pours may be required under tile or stone |
| Flow test | 10–12" with the large flow ring, 5–6" with the small ring (TDS 235) |
| Set time (ASTM C1708) | initial 20–30 min, final 35–40 min |
| Walkable | 2–3 hours at 70°F (21°C) |
| Install floor covering | non-moisture-sensitive tile and stone once walkable (about 2–3 hours); other floor coverings from 12 hours in good drying conditions (65–75°F, 40–60% RH) |
| Compressive strength | 2,500 psi at 1 day, 3,500 psi at 7 days, 5,500 psi (37.9 MPa) at 28 days (ASTM C1708 / C109) |
| Flexural / tensile bond | 840–1,100 psi flexural (ASTM C1708); 270–390 psi tensile bond (ASTM C1583), both at 28 days |
| Flammability | ASTM E84: flame spread index 0, smoke developed index 0 |
| Installed dry weight | 2.7 lb per sq ft at 1/4" (6 mm) |
| Temperature | substrate 40–90°F (4–32°C), air 50–90°F (10–32°C) during application |
| Use | interior only; not a wear surface; not for submerged areas; not over painted surfaces, waterproofing or crack isolation membranes; no rolling dynamic loads for 72 hours |
| Standard | ANSI A118.16 |
| Packaging | 55 lb bag, part 0902-0055-21, 56 per pallet (the data sheet prints "22.7 kg" here but "25 kg" in the mixing section; 55 lb is 24.9 kg); 2,500 lb (1,133.9 kg) bulk bag, part 0902-2500-21 |
What NXT Level Plus is for
NXT Level Plus is a cement-based, fiber-reinforced self-leveling underlayment from LATICRETE. You mix it with water, pour or pump it onto a primed floor, and it flows out into a flat, hard base for the floor covering on top. LATICRETE describes it as rapid setting, interior only, and a direct replacement for its older DRYTEK LEVELEX PLUS. It is an underlayment, not a wear surface.
The reason most people pick Plus over the standard NXT Level is the subfloor. The fibers let it go over APA-rated exterior-glue plywood and OSB without metal lath, starting at 1/4 inch. That saves a lathing step on renovation jobs over wood framing. The data sheet also lists concrete, cement backer board, cement mortar beds, cement terrazzo, existing ceramic tile and stone, vinyl tile, gypsum underlayments, and LATICRETE's STRATA_MAT and STRATA_HEAT Mat as suitable substrates.
How the calculator works out bags
A bag of self-leveler makes a roughly fixed volume of material, so coverage is inversely proportional to depth. LATICRETE's chart gives 24 sq ft per 55 lb bag at 1/4 inch, which is half a cubic foot. Pour twice as thick and the same bag covers half the area: 12 sq ft at 1/2 inch, 3.0 sq ft at 2 inches.
The calculator takes your area, adds the waste allowance you choose, divides by the coverage at your thickness scaled in a straight line from the 1/4 inch figure, and rounds up to whole bags. The chart has six rows. Three of them (1/4, 1/2 and 2 inches) match the straight line exactly. The other three print a touch more coverage than the line: 49 vs 48 sq ft at 1/8 inch, 8.1 vs 8.0 at 3/4 inch, 6.1 vs 6.0 at 1 inch. The calculator keeps the lower number, so on those depths it may suggest one bag more than the chart would on a big floor.
Use the average thickness, not the deepest point. Low spots, slopes toward a drain and dips around old fixtures add up quickly. If the floor varies a lot, measure it with a laser or electronic level, split it into zones and run the calculator once per zone.
Thickness rules by substrate
The minimum depth depends on what you pour over, and the calculator lets you enter anything from 1/8 to 2 inches, so pick the right figure yourself:
- Concrete: 1/8 inch to 2 inches, and it can be tapered to zero at the edges.
- Plywood or OSB: 1/4 inch to 2 inches, no lath. LATICRETE adds that thicker pours may be needed when tile or stone goes on top.
- STRATA_MAT or STRATA_HEAT Mat: at least 1/2 inch, and no primer is needed over the mat. Crack isolation properties do not apply over these mats.
Over 2 inches, the data sheet asks you to contact LATICRETE Technical Services. If your floor needs deeper fills, the standard NXT Level goes to 3 inches in one lift.
Wood subfloor requirements
Over wood the structure matters as much as the leveler. The subfloor must be APA-rated Type 1 exterior-exposure plywood or an OSB equivalent, sound enough for live, dead and impact loads. LATICRETE sets the maximum deflection at L/360 under ASTM F2873, which is also the usual limit for ceramic tile; natural stone needs L/480, and some resilient and wood flooring makers ask for more. Sand if needed, vacuum, and prime. LATICRETE is blunt that cracks over plywood and OSB are common and are not considered a product defect, so a stiff floor is the best protection.
Priming, mixing and timing
Detailed surface preparation is in LATICRETE's separate guide TDS 230. The data sheet allows only Primer Plus, Prime-N-Bond, VAPOR BAN Primer ER, or a general epoxy primer with a sand broadcast. Keep foot traffic off the primed surface. NXT Level Plus is not a vapor barrier: concrete can test up to 100% RH under ASTM F2170, but if moisture exceeds the floor covering maker's limit, apply VAPOR BAN E, VAPOR BAN ER or VAPOR BAN Primer ER first.
Mix each bag with 5.0 to 5.5 quarts of water for 2 to 3 minutes with a heavy-duty drill at 650 rpm, then check flow: 10 to 12 inches with the large ring, 5 to 6 inches with the small one. Initial set is 20 to 30 minutes and final set 35 to 40 minutes, so stage enough bags and helpers before the first pour. Keep the substrate between 40°F and 90°F and the air between 50°F and 90°F, shade the area from direct sun, and do not damp-cure or seal it.
The floor is walkable in 2 to 3 hours, and non-moisture-sensitive tile and stone can go down then. Other floor coverings can follow after 12 hours in good drying conditions (65 to 75°F, 40 to 60% RH), four hours sooner than the standard NXT Level. Cold, humid or poorly ventilated rooms and thicker pours take longer. Keep scissor lifts and other rolling loads off for 72 hours.
Limitations worth checking before you buy
Do not pour NXT Level Plus over particleboard, chipboard, hardboard, luan, asbestos, asphalt, coal tar, lightweight insulating concrete or painted surfaces. Do not pour it over waterproofing or crack isolation membranes; if a membrane is needed, it goes on top of the dry leveler. It is not for submerged areas, and steel-wheeled traffic can damage the surface before VCT, LVT or sheet vinyl goes down.
FAQ
How much does a bag of NXT Level Plus cover?
LATICRETE's data sheet DS-505-1026 gives 24 sq ft (2.3 m²) per 55 lb bag at 1/4 inch. The chart also lists 49 sq ft at 1/8 inch, 12 at 1/2 inch, 8.1 at 3/4 inch, 6.1 at 1 inch and 3.0 at 2 inches. Real coverage depends on how flat and how textured the floor is, so survey the floor and add a waste allowance before you order.
Does the calculator match LATICRETE's chart?
At 1/4, 1/2 and 2 inches it gives exactly the printed figure. At 1/8 inch the straight line gives 48 sq ft against the chart's 49, at 3/4 inch 8.0 against 8.1, and at 1 inch 6.0 against 6.1. In each of those rows the calculator assumes slightly less coverage than the chart, so the bag count errs on the high side by 1 to 2 percent.
How much water goes in a bag of NXT Level Plus?
Mix each 55 lb bag with 5.0 to 5.5 US quarts (4.7 to 5.2 L) of water. Add the powder to the water and mix for 2 to 3 minutes with a heavy-duty drill at about 650 rpm. LATICRETE warns that overwatering weakens the product and asks for a flow test: 10 to 12 inches with the large flow ring or 5 to 6 inches with the small ring.
What is the difference between NXT Level and NXT Level Plus?
NXT Level Plus comes in a 55 lb bag and covers 24 sq ft at 1/4 inch; NXT Level comes in a 50 lb bag and covers 22 sq ft. Plus is fiber reinforced and goes over plywood and OSB at 1/4 inch without metal lath, while NXT Level needs diamond lath and at least 1/2 inch over wood. NXT Level pours up to 3 inches and carries a UL fire rating; Plus is limited to 2 inches. Plus accepts most floor coverings after 12 hours instead of 16.
Can I pour NXT Level Plus over a plywood subfloor?
Yes, over APA-rated Type 1 exterior-exposure plywood or equivalent OSB, interior only, with no metal lath. The minimum is 1/4 inch over wood, and LATICRETE says thicker pours may be required under tile or stone. The floor must meet L/360 deflection (L/480 for natural stone), be clean and primed, and LATICRETE notes that cracks over plywood and OSB are expected and are not treated as a product defect.
LATICRETE and LATICRETE NXT Level Plus are trademarks of their owner. This page is an independent estimate based on the published data sheet; check the bag label before mixing.